private async void OnRefresh()
{
IsBusy = true;
await Task.Yield();
// Clear the list or you'll get duplicates upon resuming
Races.Clear();
// get the list of races
IEnumerable <Race> races = await _dataService.GetRacesAsync();
var previous = new Group <Race>()
{
Name = "Previous Races"
};
var current = new Group <Race>()
{
Name = "Current Races"
};
var future = new Group <Race>()
{
Name = "Upcoming Races"
};
var now = DateTimeOffset.Now;
foreach (var race in races)
{
if (race.StartDate > now)
{
future.Add(race);
}
else if (race.EndDate < now)
{
previous.Add(race);
}
else
{
current.Add(race);
}
}
// sort items
current.Sort(i => i.StartDate ?? DateTimeOffset.MinValue);
future.Sort(i => i.StartDate ?? DateTimeOffset.MinValue);
previous.SortDescending(i => i.EndDate ?? DateTimeOffset.MaxValue);
Races
.AddGroupIfNotEmpty(current)
.AddGroupIfNotEmpty(future)
.AddGroupIfNotEmpty(previous);
IsBusy = false;
}